The present invention relates to compact torque converter tools which are very compact and which provides a high mechanical advantage and while designed particularly for use with lug wrenches, is not limited thereto and is easily adaptable for use in numerous environments.
In the prior art, numerous efforts have been directed to providing torque converters, speed wrenches and the like utilizing various forms of gearing. In the case of lug wrenches for removing hub nuts or lug nuts from the wheels of automobiles, these required that the housing in some way be anchored to the wheel or ground to prevent their rotation during operation of the device. The present invention provides an internal braking through the use of a worm or helical gear having a high reduction ratio and having an axis transverse to the drive axis and spaced therefrom which is drivingly coupled to a bevel gear pair (a crown bevel gear and a pinion bevel gear) with one element of the bevel gear pair being rotatably mounted in the annular housing. A first coupling gear on the axis of and driven with the beveled pinion gear of the bevel gear pair is drivingly coupled to a second coupling gear which is integral with a worm-helical gear journaled for rotation in the annular housing about an axis transverse to the axis of the annular housing and spaced from the axis thereof. This second coupling gear couples the rotary movements of the beveled pinion gear means to an output torque member. The output torque member is integrally formed on the shaft of a gear which is meshed with the worm gear. The use of the worm gear is this preferred embodiment substantially prevents rotation of the housing and constrains the movement of the annular housing without requiring that the housing be restrained by some physical obstruction or by holding same.
As noted earlier, torquing or speed lug wrenches are known in the art, some of which are particularly adapted for lug wrenches such as, for example, Osmond U.S. Pat. No. 3,992,964 and Michaud U.S. Pat. No. 4,274,310 both use planetary gearing systems, some of which are tandem planetary gearings with one or more annular housing. Similarly, the gear wrench of Wagner Pat. No. Re29,993 discloses tandem planetary gear units and require that the housing have a support for holding the housing stationary relative to the shafts. Sauter U.S. Pat. No. 3,331,269 and Duchesne U.S. Pat. No. 3,208,317 relate to tools in which beveled gears are utilized and are contained in a housing that serves as the handle for supplying input torque. In Chriswell U.S. Pat. No. 2,721,591, the disclosure relates to a geared screw driver using a conventional planetary gear wherein the ring gear is formed as part of the housing. In McDonald U.S. Pat. No. 3,861,244, the torque wrench utilizes a casing having a reaction bar and a power input coming from an eccentrically arranged drive arm. The geared screw driver of Schefield Pat. No. 3,823,755 has the planetary gearing arrangement contained within the handle of the screw driver. The ratchet attachment of Taub U.S. Pat. No. 4,279,314 incorporates an energy storing attachment--e.g. a spring which is used for loosening. In Schnepel et al U.S. Pat. No. 2,510,483, a speed and power geared hand wrench and an operating handle is formed as a part of or an attachment to the housing containing the gearing mechanism and in Marsten, Jr., et al U.S. Pat. No. 2,641,136, a separate handle is provided for controlling the movement of the gear mechanism.
The present invention is an improvement over the art in that it can be manufactured more compactly and, there is no need for appurtenances for preventing or locking rotatation of the housing. The function is performed by the internal gear arrangement including the worm gear and worm wheel with high reduction ratios and combination of components.